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+8MBGMSFX.SF2
+============
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+The main SF2 used for Creative Sound Blaster Live's
+([emu10k1](/Emu10k1 "Emu10k1")).
+
+It is available on the Creative CD. Or you may download it (\~7.4 mb):
+
+[http://www.alsa-project.org/\~james/sound-fonts/8MBGMSFX.SF2](http://www.alsa-project.org/~james/sound-fonts/8MBGMSFX.SF2)
+
+Retrieved from
+"[http://alsa.opensrc.org/8MBGMSFX.SF2](http://alsa.opensrc.org/8MBGMSFX.SF2)"
+
+[Category](/Special:Categories "Special:Categories"):
+[MIDI](/Category:MIDI "Category:MIDI")
+
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+AC97
+====
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+**AC97** (short for "Audio Codec 97") is a standard
+[soundcard](/Soundcard "Soundcard") and network card interface
+Architecture developed by the Intel Corporation (back in 1997).
+Specialized hardware is available to peripheral manufacturers which
+implements the AC97 standard which has resulted in this standardized
+architecture being used in many
+[motherboards](?title=Motherboard&action=edit&redlink=1 "Motherboard (page does not exist)"),
+[modems](?title=Modem&action=edit&redlink=1 "Modem (page does not exist)"),
+and [sound
+cards](?title=Sound_card&action=edit&redlink=1 "Sound card (page does not exist)").
+
+ ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ **Note:**Intel's use of the word "codec" in "Audio Codec 97" refers to the signals being converted from [analog](?title=Analog&action=edit&redlink=1 "Analog (page does not exist)") to [digital](?title=Digital&action=edit&redlink=1 "Digital (page does not exist)") (enCOded) and from digital to analog (DECoded). This should not be confused with multimedia [codecs](?title=Codec&action=edit&redlink=1 "Codec (page does not exist)") which COmpress and DECompress video and audio data.
+ ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+
+In addition to AC97 defining control and data access functions (as well
+as a [Plug and
+play](?title=Plug_and_play&action=edit&redlink=1 "Plug and play (page does not exist)")
+setup interface), it also defines a couple standardized audio formats
+which are common to many desktop computers. This includes 16-bit and
+20-bit sample size and 48 kilohertz and 96 kilohertz sample rates for
+multichannel recording and playback.
+
+ -----------------------------------------------------------------------------------------------------------------------------------------------------
+ **Note:**In 2004, AC'97 was superseeded by the Intel's [HD Audio](?title=HD_Audio&action=edit&redlink=1 "HD Audio (page does not exist)") standard.
+ -----------------------------------------------------------------------------------------------------------------------------------------------------
+
+ -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+ **Programming note:**In addition to the audio interface, AC97 provides modem and network (Modem/LAN) interface functionality. If the Modem/LAN functions are to be used along with the audio functions, the audio device needs to be set as master and the Modem/LAN device set as slave. If the audio device is not used, the Modem/LAN should be set to be master device.
+ -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+
+External link
+
+- [Intel Audio Chipset
+ Designs](http://www.intel.com/design/chipsets/hdaudio.htm)
+
+Retrieved from
+"[http://alsa.opensrc.org/AC97](http://alsa.opensrc.org/AC97)"
+
+[Category](/Special:Categories "Special:Categories"):
+[Glossary](/Category:Glossary "Category:Glossary")
+
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+ALSA
+====
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+**ALSA** stands for **A**dvanced **L**inux **S**ound **A**rchitecture.
+It is a suite of hardware drivers, libraries and utilities which provide
+audio and MIDI functionality for the Linux operating system. ALSA is the
+main topic [this wiki](/ALSA:About "ALSA:About") is about.
+
+The official web site of the ALSA project is:
+[http://www.alsa-project.org/](http://www.alsa-project.org/)
+
+Features
+--------
+
+Sigificant features of the ALSA audio system according to their website
+include...
+
+- efficient support for all types of audio interfaces, from consumer
+ soundcards to professional multichannel audio interfaces
+- fully modularized sound drivers
+- SMP and thread-safe design
+- user space library (alsa-lib) to simplify application programming
+ and provide higher level functionality
+- support for the older OSS API, providing binary compatibility for
+ most OSS programs
+
+More features according to its users:
+
+- very stable (at least for me!)
+- much midi things working! (compared to OSS better support)
+- easy creating midi/sound editors!
+- common interface
+- support for many cards
+- nice developers! ;-)
+- sound standard for the 2.6.x Linux kernel
+- OSS emu
+- Plugin layer support in userspace
+- ALSA System on Chip layer to support Embedded audio devices
+
+mail joachim (js ATT dune2 DoTT de)
+
+Retrieved from
+"[http://alsa.opensrc.org/ALSA](http://alsa.opensrc.org/ALSA)"
+
+[Categories](/Special:Categories "Special:Categories"):
+[Software](/Category:Software "Category:Software") |
+[Glossary](/Category:Glossary "Category:Glossary")
+
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+ALSA PCM proc commands
+======================
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+By default, ALSA emulates OSS PCM with the so-called *plugin layer*,
+i.e. tries to convert the sample format, rate or channels automatically
+when the card doesn't support it natively. This will lead to some
+problems for some applications like quake or wine, especially if they
+use the card only in the MMAP mode.
+
+In such a case, you can change the behavior of the PCM per application
+by writing a command to the relavent /proc file. There is a proc file
+for each PCM stream,
+
+` `
+
+ /proc/asound/cardX/pcmY[cp]/oss
+
+- *X* is the card number (starting from zero; the first card is card
+ 0, the second card is card 1, etc.)
+- *Y* is the PCM device number (also starting from zero)
+- *p* is for playback and *c* for capture, respectively.
+
+Note that this proc file exists only after snd-pcm-oss module is loaded.
+
+The command sequence has the following syntax:
+
+` `
+
+ app_name fragments fragment_size [options]
+
+- *app\_name* is the name of application with (higher priority) or
+ without path.
+- *fragments* specifies the number of fragments or zero if no specific
+ number is given.
+- *fragment\_size* is the size of fragment in bytes or zero if not
+ given.
+- *options* is the optional parameters.
+
+The following options are available:
+
+- disable -- The application tries to open a pcm device for this
+ channel but does not want to use it.
+- direct -- Don't use plugins
+- block -- Force block open mode
+- non-block -- Force non-block open mode
+
+The *disable* option is useful when one stream direction (playback or
+capture) is not handled correctly by the application although the
+hardware itself does support both directions.
+
+The *direct* option is used, as mentioned above, to bypass the automatic
+conversion and useful for MMAP-applications. For example, to playback
+the first PCM device without plugins for quake, send a command to the
+relevant /proc "file" via echo like the following:
+
+` `
+
+ % echo "quake 0 0 direct" > /proc/asound/card0/pcm0p/oss
+
+While quake wants only playback, you may append the second command to
+notify the driver that only this direction is about to be allocated:
+
+` `
+
+ % echo "quake 0 0 disable" > /proc/asound/card0/pcm0c/oss
+
+The permissions of /proc files depend on the module options of ((snd)).
+As a default it's set as root, so you'll likely need to be superuser for
+sending the command above.
+
+The *block* and *non-block* options are used to change the behavior of
+opening the device file. As default, ALSA behaves as defined in POSIX,
+i.e. blocks the file when it's busy until the device becomes free
+(unless O\_NONBLOCK is specified). Some applications assume the
+non-block open behavior, which are actually implemented in some real OSS
+drivers.
+
+This blocking behavior can be changed globally via nonblock\_open module
+option of snd-pcm-oss. For using the non-block mode as default for OSS
+devices, define like the following:
+
+` `
+
+ options snd-pcm-oss nonblock_open=1
+
+You can check the currently defined configuration by reading the proc
+file. The read image can be sent to the proc file again, hence you can
+save the current configuration
+
+` `
+
+ % cat /proc/asound/card0/pcm0p/oss > /somewhere/oss-cfg
+
+and restore it like
+
+` `
+
+ % cat /somewhere/oss-cfg > /proc/asound/card0/pcm0p/oss
+
+Also, for clearing all the current configuration, send erase command as
+below:
+
+` `
+
+ % echo "erase" > /proc/asound/card0/pcm0p/oss
+
+Retrieved from
+"[http://alsa.opensrc.org/ALSA\_PCM\_proc\_commands](http://alsa.opensrc.org/ALSA_PCM_proc_commands)"
+
+[Category](/Special:Categories "Special:Categories"):
+[Documentation](/Category:Documentation "Category:Documentation")
+
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+ALSA Setup Guide
+================
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+[ToDo]: include base information common for all the distros ( we can use
+the simulation package installation; i.e. instead of use!
+
+ apt-get install alsa-utils
+
+we can use
+
+ binary-package install alsa-utils
+
+This convention advoid specific distro complications. You can go to your
+distro documentation (or we can include here links ) about how to
+install a package. This doesn't, of course, address things like init
+scripts which are managed in widely different ways on different distros.
+
+Gentoo's ALSA documentation
+---------------------------
+
+[http://www.gentoo.org/doc/en/alsa-guide.xml](http://www.gentoo.org/doc/en/alsa-guide.xml)
+Page is pretty specific to Gentoo. References the Gentoo specific
+commands to install Gentoo specific scripts which do Gentoo specific
+things (like the gentoo init-scripts, which are distribution specific),
+none of which have links to any explanations.
+
+Has some general description of using with the now dying DEVFS (kernel
+2.6.x suggests not using DEVFS anymore). udev / 2.6 kernel systems (now
+the default) will generally just work first time, as the insersion of
+the sound modules creates hotplug events which cause udev to create the
+device nodes.
+
+Retrieved from
+"[http://alsa.opensrc.org/ALSA\_Setup\_Guide](http://alsa.opensrc.org/ALSA_Setup_Guide)"
+
+[Category](/Special:Categories "Special:Categories"):
+[Installation](/Category:Installation "Category:Installation")
+
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+ALSA device labels
+==================
+
+### From the ALSA wiki
+
+Jump to: [navigation](#mw-head), [search](#p-search)
+
+When you issue commands such as `aplay` or `arecord`, the commands may
+need to be told which ALSA devices you want them to use.
+
+**Example:**
+
+If your sound card has two devices to play back sound (say, one analog
+for your PC speakers, and another digital, using an
+[S/PDIF](/S/PDIF "S/PDIF") connection to your stereo), `aplay` will
+probably default to using the analog device. If you want it to use the
+digital device, you'll need to tell it to do so.
+
+An ALSA device label generally looks something like `hw:0,0` for the
+first hardware PCM device, `default:0` for the device configured as the
+default (which in a vanilla 1.0.11 configuration is a
+[dmix](/Dmix "Dmix")'ed version of `hw:0,0`, etc.).
+
+You can get a list of all available playback pcm devices along with
+their definitions by using the command
+
+` `
+
+ aplay -L
+
+**See also:**
+
+- [How can I see which audio [pcm], midi [seq] and mixer [ctl] devices
+ my ALSA installation
+ sees?](/FAQ#How_can_I_see_which_audio_.5Bpcm.5D.2C_midi_.5Bseq.5D_and_mixer_.5Bctl.5D_devices_my_ALSA_installation_sees.3F "FAQ")
+- [Proc asound
+ documentation](/Proc_asound_documentation "Proc asound documentation")
+- [Some notes on dealing with /proc from
+ Takashi](/AlsaTips#Some_notes_on_dealing_with_.2Fproc_from_Takashi_.282.29 "AlsaTips")
+
+Retrieved from
+"[http://alsa.opensrc.org/ALSA\_device\_labels](http://alsa.opensrc.org/ALSA_device_labels)"
+
+[Category](/Special:Categories "Special:Categories"):
+[Documentation](/Category:Documentation "Category:Documentation")
+
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